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POstrtok and memory leaks
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copied!<p>I wrote a simple url parser using strtok(). here's the code</p> <pre><code>#include <stdio.h> #include <stdlib.h> typedef struct { char *protocol; char *host; int port; char *path; } aUrl; void parse_url(char *url, aUrl *ret) { printf("Parsing %s\n", url); char *tmp = (char *)_strdup(url); //char *protocol, *host, *port, *path; int len = 0; // protocol agora eh por exemplo http: ou https: ret->protocol = (char *) strtok(tmp, "/"); len = strlen(ret->protocol) + 2; ret->host = (char *) strtok(NULL, "/"); len += strlen(ret->host); //printf("char at %d => %c", len, url[len]); ret->path = (char *)_strdup(&url[len]); ret->path = (char *) strtok(ret->path, "#"); ret->protocol = (char *) strtok(ret->protocol, ":"); // host agora é por exemplo address.com:8080 //tmp = (char *)_strdup(host); //strtok(tmp, ":"); ret->host = (char *) strtok(ret->host, ":"); tmp = (char *) strtok(NULL, ":"); if(tmp == NULL) { if(strcmp(ret->protocol, "http") == 0) { ret->port = 80; } else if(strcmp(ret->protocol, "https") == 0) { ret->port = 443; } } else { ret->port = atoi(tmp); } //host = (char *) strtok(NULL, "/"); } /* * */ int main(int argc, char** argv) { printf("hello moto\n"); aUrl myUrl; parse_url("http://teste.com/Teste/asdf#coisa", &myUrl); printf("protocol is %s\nhost is %s\nport is %d\npath is %s\n", myUrl.protocol, myUrl.host, myUrl.port, myUrl.path); return (EXIT_SUCCESS); } </code></pre> <p>As you can see, I use strtok() a lot so I can "slice" the url. I don't need to support urls different than http or https so the way it's done solves all of my problems. My concern is (this is running on an embedded device) - Am I wasting memory ? When I write something like</p> <pre><code>ret->protocol = (char *) strtok(tmp, "/"); </code></pre> <p>And then later call </p> <pre><code>ret->protocol = (char *) strtok(ret->protocol, ":"); </code></pre> <p>Does me first pointer ret->protocol held remain in memory ? I thought that maybe I should set the first call to a tmp pointer, call strtok pointing ret->protocol to the right portion of the string (the second call) and then free(tmp).</p> <p>What should be the best way to use strtok ?</p>

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